Glow lamp



Aug, 7, 1934. T KQWVALUS 1,969,566

THEODORE KOWVALLIS Kyu/@MIO Patented Aug.l 7, 1934 UNITED STATESI PATENT GLOW LAMP Theodore Kowvalli's, Rea-ding, Pa., assgnor of iifty per cent to Berkmont Company, a. corporation of Delaware This invention relates to gaseous conduction lamps and more particularly to lamps'of that character in which illumination is obtained by an electric discharge caused to pass from one B to the other of two electrodes in a sealed enclosure containing a rarefied gas or vapor.

Among the principal objects of the present invention is to provide a gaseous conduction lamp, otherwise known as a glow discharge lamp,

which is adapted for operation with either direct or alternating current at commonly available voltages. y

The broad idea of providing electric glow dis-V charge lamps for illuminating purposes is, of l5 course, not new and various attemptsA have been made from time to time to provide a lamp in which thegas or vapor is rendered luminous by the discharge of current passing from one to the other of two electrodes sealed within the enclosure containing the gas or vapor.

One of the earliest forms of glow tubes was that known as the Geissler wherein a glow dis-v charge was produced by the passage of an elec-- tric current through a gas of low pressure.

Experimenters have observed that in such types of glowtubes the surface of the negative electrode or cathode was surrounded by a very thin layer of luminosity; next to this very limited zone of luminosity was a `dark space called Crookes dark space. Immediately beyond this dark space was a luminous zone called the negative glow; and beyond this luminous zone was a second dark region, sometimes referred to as the Faradaydark space. Between this Faraday dark space and the positive elect-rode or anode was the luminous region termed the positive column. It is among the principal objects of this invention to construct a gaseous conduction lamp wherein the negative and positive electrodes are so related in space and are so constructed that the non-luminous region known as the Crookes dark space is reduced to a substantially irreducible minimum in consequence of which the principal luminous discharge in the lamp lis that which is obtained from the so-called negative glow.

Further objects of the invention are to provide a glow discharge lamp wherein the space relation and design of the positive and negative electrodes are such that it becomes possible to operate the lamp at relatively low voltages and by this'is meant voltages which are comparable with those now in general use; to eliminate the necessity of interrupters, special inductive circuits and other devices for creating and maintaining the discharge at such relatively low voltages; and to provide for a maximum luminosity when the electric current, either direct or alternating, is discharged between the electrodes of the lamp and through the gas sealed therein.

Still another object of the invention is to pro- 'vide in a gaseous conduction lamp ofthe character described a plurality of sets of positive and rnegative electrodes uniformly spaced within the Ation thereof will-be apparent morefully hereinafter.

The invention consists substantially in the combination, construction, arrangement and relative location of parts, au as w111 be described 80 more fully hereinafter, as shown in the accompanying drawing, and as finally pointed out in the appended claims. l l .j

In the accompanying drawingzr Figure 1 is an elevational view of the lamp con- 85 structed in accordance with the principles of the present invention; y -f Figure 2 is a vertical sectional view of the lamp taken on the line 2.-2 of Figure r1;

Figures 3 and 4 are horizontal cross-sectional 90 views taken respectively on the lines 3 3 and 4 4 of Figure 1; l 1` Figure 5 is a perspective view of the lamp,

a portion. of the exterior bulb being broken away to more clearly show the internal construction thereof. l

Referring now more particularly to the drawing, a lamp constructed in accordance with the v present invention comprises an exterior bulb 10 of transparent glass, this exterior bulb be- 100 ing of any desired conguration but preferably of a configuration having a reduced neck 11 and anenlarged main body 12 the lower or outer end' of which is drawn to a point and sealed, as lat 13. Y

Disposed within the interior 'of the bulb 10 is a bulb 14 also constructedof glass and provided with an elongated, reduced neck 15, the lower end of the bulb 14 being sealed, as at 16. The upper ends of the concentrically arranged necks no 11 and 15 are integrally united together, as at 1'7, preferably by fusing the glass togeth'er, thereby providing a unitary lamp assembly within which is provided an hermetically sealed chamber 18 adapted to be filled with a suitable gas or vapor of the helium or argon4 groups. Or the chamber 18 may be filled with a monatomic gas, such as neon, or any other gas or combination of gases which become luminous when an electric current is discharged therethrough, regardless whether the current is direct or alternating. The pressure of the gas contained within the chamber 18 may vary as desired and may range from 1 to 30 m. m. of mercury, the correct pressure of the gas contained within the chamber 18 being dependent upon the relative relation of the electrodes containedtherein as well as upon the nature, shape, cross-sectional area, length, and number vof the electrodes sealed within the gas-containing chamber 18.

The internal bulb 14, as employed in the lamp ofthe present invention, serves a triple function. In the first place, it serves as the supporting post for the several sets of electrodes to be presently described. In the second place, it serves Athe important function ofcontrolling and regulating the volumetric' capacity of the chamber 18. In the third place, it affords a very convenient'means for providing in the center of the lamp a reflecting -medium or surface for affording a more uniform dispersion or distribution of the light emanating from the-lamp. y

Referring again more particularly to the drawing, it will be observed that the inner bulb 14 is provided at opposite extremities of the bulbous portion thereof with a plurality of substantially radially extending anchors 19 of insulating material. Preferably, these anchors 19 are each formed ofr glass fused' or otherwise integrally united to the bulb 14 constituting the support therefor. It will be observed that eachy of these anchors 19 comprises a radially extending Asectiony 20, a laterally turned section 21 and a longitudinallyv turned section 22. It will further be observed that the upper set of anchors 19` are so circumferentially spaced with respect to the lower set of anchors 19 that the longitudinally turned sections 22 of the upper set of anchors are respectively in 'Vertical alignment with the outer extremities of the radially extending sections-20 of the lower set ofLanchors 19. Also, the upwardly turned sections 22 of the lowerset ofanchors 19 are respectively invertical alignf theinner bulb 14 are a pair of conductor wires 23A ment with the outer extremities of the radially extending sections 20 of the upper set of anchors. y

Extended downwardly through the center of and 24. Conductor wire 23 is extended to a point adjacent the lower end of the inner tube 14, as at 25, while conductor'wire 24 is extended only to a point adjacent the lower end of the neck 15 of 'the inner bulb, asA at 26. Secured to each oi!V the. upper set of anchors 19 are a pair of electric terminals 27a and 28a, while secured to each n anchored to the free extremities of the anchors '19; lEach anchor thus constitutes a support for a pair of electrode terminals and in addition serves to maintain each such pair of electrode terminals in insulated. and iixedrelation. Interconnecting each set of vertically aligned electrode terminals d2'7a is an electrode 29, while interconnecting each set of vertically aligned electrode terminals 28a and 28h is an electrode 30. 'I'he electrodes29 may constituteithe positive electrode or anode, in which case the electrodes 30 constitute the negative electrodes or cathodes of the lamp. Suitably supported by the upper set of anchors 19 and electrically interconnecting each of the upper terminals 27a of the positive electrodes 29 is a wire'31 which in turn is connected to the conductor wire 24, it being observed that the wire 3l is insulated from the upper terminals 28a of the electrodes 30. Similarly, the lower set of anchors 19 support a wire 32 to which are electrically connected the electrode terminals 28h, this wire 32being in turn connected tothe conductor wire 23.-

It will be observed that the electrodes 29 and 30 are arranged in sets circumferentially spaced about the inner bulb 14 and furthermore that the electrodes'29 and 30 of each such set are arranged in substantially parallel ancliixed relation. Also, the radially extending sections 20 of the anchors are of such length as to position the electrodes 29 and 30 substantially equidistantly from the walls of the bulbs 10 and 14.

If desired, and demonstration has proved it to be desirable, the inner surface of the internal bulb 14 may be silvered or otherwise provided with ay reiiecting medium, to vafford a more uniform and greater distribution of light from the lamp. A lamp thus constructed will be operated either on direct or alternating current., As a suitable material for the electrodes 29 and 30, tungsten has been found to be quite satisfactory. Also, it has been found that the lamp operates satisfactorily with the positive electrodes formed of nickel and the negative electrodes formed of molybdenum cr platinum. g

. In order that a lamp as above described may be' `readily employed in direct current supply systhe conductor wires 23 and 24 may be connected f in the usual manner. In operation, when current of ordinary commercial voltage is'supplied to the electrodes 29 and 30 through the conductor wires 23 and 24 and the electrode connecting wires 31 and 32, an electric discharge will be produced between each set of electrodes 29 and 30, the said discharge being coextensive in length with that oi' the electrodes and becauseof this extensive electric discharge substantially all of the gas contained in the lamp is rendered luminous.

It will be understood, of course, that the invention is susceptible of various changes and modifications which may be made from time to time without, departing from the general principles or 4real spirit thereof and it is accordingly intended to claim the invention broadly, as well as specifically, as indicated by the appended claims.

What is claimed as new and useful is:-

1. In a gaseous conductionlamp, in combination, a pair oi glass bulbs arranged one within the other to provide a sealed chamber between the walls thereof, the volumetric capacity of said chamber being regulated by the size of the inner glass bulb, a plurality of pairs of electrodes disposed within said chamber, each oi' said pairs of electrodes consisting of a positive and a negative electrode, and means extending radially from opposite ends of the inner bulb for supporting said pairs of electrodes in circumferentially spaced relation within said chamber and substantially equidistant from the axis of said inner bulb.

2. In a gaseous conduction lamp, in combination, a pair o1' glass bulbs arranged one within the other to provide a sealed chamber of predeterminedly xed volumetric capacity, said chamber being adapted to be lled with an Aelectrically conductive gas, a plurality of radially extending electrodeanchors secured to the inner bulb adjacent opposite extremities thereof, each of said anchors extending well within said chamber, a pair of electrodes of opposite polarity supported by and extending between each set of vertically aligned anchors, the upper ends of all of the electrodes of one polarity being commonly connected to a conductor wire extending upwardly through the interior of the inner bulb and the lower ends of all of the electrodes of opposite polarity being similarly commonly connected to a conductor wire also leading upwardly through the interior of said inner bulb. f

3. In a gaseous conduction lamp, in combination, a lpair of bulbs arranged one within the -other to provide a sealed chamber between the walls thereof of predeterminedly xed volumetric capacity, said chamber being adapted to be lled with an electrically conductive gas, a plurality of sets of anodes and cathodes arranged within said chamber at circumferentially spaced intervals,

and a plurality of insulating anchors carried by the inner bulb adjacent the upper and lower ends thereof for supporting said anodes and cathodes in xed relation within said chamber, the upper anchors being respectively in vertical alignment with the lower anchors and each pair of vertically aligned upper and lower anchors being adapted to support, inv insulated relation and substantially equidistantly from the axis of the inner bulb, a pair of said anodes and cathodes.

4. In a gaseous conduction lamp, in combination, an exterior bulb adapted to be lled with gas of relatively high electrical conductivity, an inner bulb arranged within said exterior bulb for reducing the gas content of the lamp, said bulbs being relatively so arranged as to provide a substantially elongated annular chamber predeterminedly fixed volumetric capacity within which said gas is sealed, and a plurality of sets of electrodes of opposite polarity arranged within said chamber at circumferentially spaced intervals, each set of positive and negative electrodes being arranged in parallel relation and substantially equidistantly from the axis of the inner bulb whereby to provide a gaseous discharge therebetween upon the application of a relatively low voltage there- THEODORE KOWVALLIS. 

